In a molding process for molding a clamp having a hinge structure by resin, the mold may include a first mold part for molding a hinge pin and a second mold part for molding a component having a bearing hole so that the entire hinge structure may be molded by a single-shot molding process. In such a case, for the hinge pin and the component defining the bearing hole to be molded at the same time, a certain gap is required between the hinge pin and the bearing hole. Therefore, a certain amount of play is inevitable between the hinge pin and the bearing hole.
JPS63-77184U and JP2002-128112A disclose a clamp for securing piping on a lower side of a vehicle body, and these clamps are provided with a hinge structure in which a hinge pin is loosely received in a bearing hole. According to these prior inventions, the clamp includes a base member, and a lid member connected to the base member via a hinge so as to be movable between a closed position and an open position. In the case of the clamp disclosed in JPS63-77184U, an engagement claw provided on the lid member engages a corresponding stopper provided on the base member in the closed position of the clamp so that the lid member is not only retained in the closed position, but also the engagement claw is prevented from moving laterally (along the axial direction of the hinge pin). Thereby, the movement of the lid member relative to the base member in the closed position of the clamp can be avoided. In the case of the clamp disclosed in JP2002-128112A, a latch consisting of engagement features provided on the outer surface of the hinge pin and the inner surface of the bearing hole is provided between the lid member and the base member so as to be engaged in the closed position of the clamp. Therefore, once the clamp is closed, the movement of the lid member relative to the base member can be avoided.
Thus, according to these previously proposed clamps, the movement of the lid member relative to the base member can be prevented when the clamp is closed or is clamping an object such as a pipe, but the lid member is freely movable relative to the base member (in directions orthogonal to the axis of the hinge pin) before the clamp is closed. Therefore, during the process of closing the clamp, the lid member is movable relative to the base member so that the latch may not be engaged in a reliable manner, and/or the lid member and the base member may not be properly positioned relative to the object to be clamped such as a pipe. In particular, the work efficiency in closing the clamp may be impaired because the worker is required to pay attention to the positioning of the lid member relative to the base member when closing the clamp.